Is it safe to take fish oil supplements when pregnant?

The answer here is yes and no! It is important to know the differences between different types of fish oil supplements.

There are two categories of fish oil supplement, one of which is safe to take in pregnancy, the other is not:

Omega-3 supplements made from the body of fish - are safe to take in pregnancy.

Cod liver oil supplements or any fish oil made from the liver of fish - are not safe to take in pregnancy.

Both types of fish oil supplements contain beneficial Omega-3 fatty acids which play a role in foetal growth and development, and are particularly essential for brain and nervous system development.

However, cod liver oil also contains high levels of the retinol form of vitamin A. You shouldn't take supplements containing the retinol form of vitamin A when you're pregnant, because large amounts of retinol can harm your baby.

Scientific studies show Omega-3's play a key role in pregnancy

There's no official recommendation that pregnant women should take a fish oil supplement but increasing numbers of studies are backing the key role of Omega-3's during pregnancy.

Some research has shown that in countries where pregnant women tend to eat more fish, fewer develop pre-eclampsia, or have a baby who is premature, or a low birth weight.

A recent study has found that a specific type of omega-3 fatty acid - docosahexaenoic acid (DHA), improves a baby's brain development. Two other studies on omega-3 fatty acids found that pregnant women who consume Omega-3s give birth to babies with a lower risk of food allergies and eczema.

A study published in the American Journal Of Clinical Nutrition credits Omega-3 fatty acids with producing children with better verbal intelligence and finer motor skills, as well as a higher pro-social behaviour. Using two blood samples, taken from 2000 women when they were 20 weeks pregnant and from the umbilical cord at birth, Professor Cristina Campoy Folgoso evaluated the effects of expecting women’s consumption of omega-3 and omega-6 fatty acids on foetal development. The study revealed that the amount of DHA transmitted to the foetus through the placenta might be crucial for foetal development.

Food sources of Omega-3

The best source of omega-3 comes from the fats found in cold-water fish such as salmon, sardines, tuna and trout, all of which have low mercury levels. Along with more general health guidelines on oily fish it is recommended you eat oily fish three times a week, as well as taking a daily omega-3 supplement.

Some types of fish contain high levels of heavy metals, such as mercury, that can affect your growing baby's health (these include tuna and swordfish) and should be avoided during pregnancy.

For people who don't eat fish, smaller amounts of omega-3 occur in foods such as eggs, soy milk and walnuts.